The proposed work focusses on the processes basic to efficient reading. The research takes advantage of the fact that Serbo-Croatian, the language of Yugoslavia, uses two alphabets, the Cyrillic and the Roman, both of which are entirely phonetic and each of which is read with equal facility by many Yugoslavs. It is now proposed to apply information processing theory and methods to processes that underlie the initial stages of reading. The research will focuss on early stages of the visual input of linguistic materials, i.e. letters, words, and nonsense letter strings, drawn from written forms of Serbo-Croatian. The emphasis will be on the processing relation between two separately acquired and used symbol systems, the organization and accessing of the internal lexicon, the units of recoding from visual to phonetic form, and the liquistic level at which visual inputs merge into the special processes of speech. The studies have special advantages for comparisons with English, since the Serbo-Croatina language situation offers "exceptional opportunities" in visual information processing: 1. there is a single spoken language, but two alphabets (Cyrillic and Roman) which are used interchangeably by substantial parts of the population. 2. The script systems are regularly phonemic, i.e., there is a one-to-one correspondence of letter to sound, 3. some of the letter shapes (about a third) are common to the two alphabets, and of these letters, some have the same sounds but some do not, and 4. schools introduce both alphabets at an early age, with Cyrillic taught first in some areas and Roman first in other areas of Yugoslavia.